Calcified vessels don’t always cause a disruption in blood flow. But when a flow-limiting calcified lesion is present, the fix usually isn’t merely a simple balloon and/or stent. To obtain an optimal result, debulking of the calcium is usually a must. In the past, rotational atherectomy was the best option. However, the learning curve for these devices can be steep, and complications are not that uncommon.
But the tides are changing — and in rolls Shockwave Medical. To break up calcified lesions, Shockwave Medical is utilizing lithotripsy. This technology, which has been around for years, uses high-energy sound waves or shock waves to break apart calcifications — most commonly, kidney stones. For these procedures, extracorporeal (outside the body) shock wave lithotripsy (ESWL) is most frequently used.
Lithotripsy delivered via catheter
Shockwave Medical uses balloon catheter-delivered intravascular lithotripsy (IVL) to target and break apart calcium within the vessel walls. Shockwave Medical received the first 510(k) approval for its device in August 2016; the latest 510(k) approval for its M5 Peripheral shockwave system device was received in June 2018.
According to the FDA’s 510(k) premarket notification letter dated September 14, 2016, approval was based on the outcomes of the PAD I and PAD II clinical trials. These studies met their primary safety and effectiveness endpoints and had favorable secondary safety and effectiveness endpoints. The device is currently approved in the U.S. for use in the iliac, femoral, ilio-femoral, popliteal, infra-popliteal, and renal arteries.
Extending use to coronary vessels
With the successful U.S. launch of its peripheral IVL, Shockwave Medical looks to extend its product usage to the coronary vasculature. The company states that the “therapy holds tremendous potential from a safety perspective for patients and ease of use perspective for physicians—if coronary IVL is shown to be safe and effective, it could be a game changer for the way we treat calcified arteries today.”
Shockwave Medical has started Disrupt CAD III clinical trial aimed at securing FDA approval of the Shockwave Coronary IVL System. The trial began on January 9, 2019, with an estimated completion date in July 2022. With favorable results from the CAD I trial, the Shockwave Coronary IVL System was approved in Europe.
Currently, the CAD II study is also underway in Europe. That study, which began on May 2018, is expected to be completed on May 30, 2019.
A potential game changer
According to the National Center for Bioethanol Information, aortic stenosis is one of the most common valvulopathologies in the Western world. As a result, Shockwave Medical is seeing a future with IVL’S potential in treating that condition. Although the product is currently in the R&D phase, its success could prove to be a game changer in the treatment of calcified valves.
As with any medical technology, results—especially long-term results—are what determine whether the technology stays afloat or sinks. Since ESWL is known to influence adjacent structures, it will be interesting to see if IVL is prone to the same, especially when used in the coronary vasculature. Cardiac arrhythmias, as well as dissections of the more fragile coronary vessels, are potential complications to watch for.